Filling apparatus for slush-molding



Feb. 17,1970 J. F. ADAMIK 3,495,742

FILLING APPARATUS FOR SLUSH-MOLDING Filed Feb. 8. 1967 INVENTOR.JAROSLAV E ADAMIK ATTORNEYS United States Patent FILLING APPARATUS FORSLUSH-MOLDING Jaroslav F. Adamik, Warren, R.I., assignor, by mesneassignments, to Marbill Company, Providence, R.I., a

corporation of Rhode Island Filed Feb. 8, 1967, Ser. No. 614,620 Int.Cl. G01f 11/00; B67d 3/26; B2913 1/00 US. Cl. 222-309 Claims ABSTRACT OFTHE DISCLOSURE Filling apparatus for introducing predeterminedquantities of plastisol into hollow molds in the art of slushmoldingcomprising a plurality of nozzles, metering cylinders containing pistonsmovable in one direction to induce plastisol into the cylinders and inthe other direction to discharge it therefrom through the nozzles, and aplurality of gauge pins selectively positionable in the path of movementof the pistons to limit their inductive movement and hence the quantityof plastisol induced.

BACKGROUND OF THE INVENTION This apparatus relates specifically to thefilling apparatus described in my pending application Ser. No. 625,678,filed Mar. 24, 1967, and as pointed out therein one of the objects wasto supply additional plastisol to the interiors of the already partiallycured articles to reinforce certain areas thereof and, in particular, inthe manufacture of footwear to reinforcing the heel, shank and counterareas. Since plastisol in excess of that required to coat these areascannot be poured out without spoiling the already formed interiorsurface of the article, it is the purpose of this invention to limit thequantity of plastisol charged into the mold at this stage in themanufacture of the article to the exact amount required to coat theaforesaid areas so that no plastisol need be dumped out.

SUMMARY As herein illustrated, the apparatus comprises a plurality ofnozzles, means supporting the nozzles for movement to a positionadjacent the open tops of hollow molds, a valve in each of the nozzlescontrolling the flow of plastisol through it, metering means connectedto a source of plastisol and to the nozzles operable to draw in apredetermined quantity of plastisol from the source and deliver it tothe nozzles, and means operable simultaneously with the delivery of themetered quantity of plastisol to the nozzles to open the valves therein.The metering means comprise pumps having intake and discharge openings,check valves associated with the intake and discharge openings operableto permit the plastisol to be drawn into the pumps and to be dischargedfrom the pumps respectively, and means for effecting operation of thepumps. Each pump comprises cylinders containing pistons operable in onedirection to induce plastisol and in the other direction to dischargeplastisol, and there is means for controlling the length of theinduction stroke and hence the volume of the plastisol drawn into thepump cylinder. The means for controlling the length of the stroke of thepistons in the induction stroke comprise a plurality of gauge pins, andmeans for moving a selected one of the gauge pins into a position tolimit the induction stroke. The nozzles are supported for movement froma retracted position to a position adjacent the upper ends of the molds,there are valves in the nozzles and switch means operative by movementof the nozzles to the positions adjacent the open tops of the molds toeffect opening of the valves.

The invention will now be described with reference to the accompanyingdrawings wherein:

FIG. 1 is a perspective of the filling apparatus;

FIG. 2 is an elevation, partly in section, of a support for holding ahollow mold in an upright position adjacent the discharge end of anozzle of the filling apparatus; and

FIG. 3 is a fragmentary section of a discharge nozzle, valve and valveoperating means.

The filling apparatus herein disclosed is employed for injecting apredetermined quantity of plastisol into a hollow mold M which alreadyhas in it a partially cured layer of plastisol for the purpose ofapplying reinforcing layers to the inner side of the partially curedlayer specifically to the counter, shank and heel pocket. The apparatusis used in conjunction with the slush-molding machine disclosed in mypending application Ser. No. 625,678, filed Mar. 24, 1967, the latterbeing provided with a rotor by means of which the molds are supportedfor movement to a position adjacent the filling apparatus. A portion ofthe rotor support is shown at A (FIG. 2) including clamping means B bymeans of which the mold is attached thereto and held in an uprightposition with its open top subjacent an injection nozzle.

There are four injection nozzles 10 supported at the upper end of apedestal 12, the lower end of which is lagged to the floor. The nozzlesare mounted for movement from a retracted position above and laterallyof the supported molds at the top of the pedestal on a cap plate 14 bymeans of a rocker arm 16 mounted on a shaft 18 journaled in bearings 20fixed to the cap plate for tilting movement about a horizontal axis andfor movement forwardly and rearwardly with a bracket member 22 securedto the forward end of a slide plate 24, the latter resting on the rockerarm and being slidably connected thereto by bolts extending through itand through slots in the rocker arm.

Rocking and sliding movement of the rocker arm and slide plate areeffected by power-operable means 26 and 28. The power-operable means 26comprises a cylinder 30 pivotally connected by a pin 32 to the pedestaland a rod 34 extending from the cylinder and pivotally connected at itsdistal end by a pin 36 to the forward end of the rocker arm. Thepower-operable means 28 is a cylinder 38 pivotally connected by a pin 40to the rear end of the rocker arm and a rod 42 extending therefrom andconnected at its distal end by a pin 44 to the slide plate 24. Thepower-operable means are double-acting so that pressure supplied to thelower end of the cylinder 26, as shown, will extend the rod 34 and henceraise the rocker arm and pressure supplied to the upper end will retractthe rod and hence lower the rocker arm. Pressure supplied to the rearend of the cylinder 38 will extend the rod 42 and thus advance the slideplate forwardly on the rocker arm and pressure supplied to the forwardend of the cylinder 38 will retract the rod and hence move the slideplate rearwardly on the rocker arm. Pressure is supplied to thecylinders 26 and 38 simultaneously so as to effect movement of the slideplate forwardly and the rocker arm downwardly to move the nozzles 10from their retracted position to a position above the open ends of themolds.

Plastisol is supplied to the nozzles 10 in predetermined quantities bymetering means 46 comprising tandemly arranged chambers 46a and 4612containing pistons (not shown). The piston in the chamber 46a isconnected to the piston in the chamber 461) and is movable by the latterdownwardly in the chamber 46a to induct plastisol and upwardly in thechamber 46a to discharge it. There are two metering means 46, onemounted at each side of the pedestal on a plate 48 extending downwardlyfrom the cap plate 14 and each is connected to a source of plastisol forsupplying a predetermined quantity of plastisol to two of the nozzles10. A single conductor 50 supplies plastisol from the source through acoupling 52 to the upper end of the chamber 46a and the couplingcontains a check valve which admits plastisol through it to the chamberwhen the piston therein is moving downwardly and checks it when thepiston is moving upwardly. The upper end of each chamber 46a isconnected by a double coupling 54 and two conductors 56 to two of thenozzle 10. The double coupling contains a check valve which permits theplastisol to flow from the chamber 46a through the conductors 56 upondischarge, that is, upward .movement of the piston in the chamber 46aand prevents retraction of plastisol in the conductors 56 on thedownward stroke of the piston in the chamber 46a.

The quantity of plastisol drawn into the chamber 46a is controlled andmay be set to the desired amount by means of gauge pins 56 which aresupported at the lower end of the metering means on a circular plate 58.The plate 58 is fixed to the upper end of a shaft 60, journaled in aframe 62, in spaced parallel relation to the axis of a piston rod 64extending through the lower end of the chamber 46b from the pistontherein. The gauge pins 56 are disposed in a circle about the axis ofthe shaft 60, the radius of which corresponds to the distance betweenthe axis of the shaft 60 and the axis of the piston rod 64 so that byrotating the plate the pins may be moved to a position directly belowthe lower end of the piston rod 64. The pins are graduated in lengthfrom the shortest which is shown at the right side of the piston rod tothe longest which is shown at the left-hand side to provide for limitingthe movement of the piston in the chamber 46b and hence the quantity ofplastisol that may be drawn into the chamber 46a. There is a spacebetween the shortest and the longest so that the piston rod may be movedto its extreme position and thereby fill the entire chamber 46a. Theshaft 60 has on its lower end within the bracket member 62 a sprocket(not shown) about which one end of a chain 66 is entrained, the oppositeend of the chain being entrained about sprocket 68 secured to the shaft70 of a motor 72. There is also on the shaft a disc carrying a pluralityof contacts corresponding in number to the pins so that it is possiblyby programming to start the motor to effect rotation of the plate 58 andto stop it with a specific pin beneath the lower end of the piston rod64 by grounding the contact representing that pin.

Discharge of a predetermined quantity of plastisol as determined by thegauging pin selected is effected by opening valves in the nozzles 10substantially simultaneously with the movement of the nozzles forwardlyand downwardly into positions above the open ends of the molds. Eachnozzle contains a ball valve 74 (FIG. 3) in which there is a diametricalhole 76 and has fixed to it a stem 78 by means of which the ball valvemay be rotated to dispose the hole across the nozzle or in alignmentwith the passage 80 therethrough. The stem extend rearwardly from thenozzles and are connected to forwardly extending shafts 82 journaled inthe lower ends of a plural ity of cylinders 84 which contain pistons andfrom the lower end of which extends piston rods 86. Each rod has on it arack 88 and each shaft has on it a gear 89 meshing with the rack so thatmovement of the piston downwardly in the cylinder through the rack, gearand shaft eifects rotation of the spindle and hence the valve in thenozzle to a position for discharge and movement in the piston in theopposite direction eflects rotation of the valve in a direction to closethe passage through the nozzle.

Pressure for moving the pistons downwardly in supplied to the upper endsof the cylinders through conductors 90 and to the lower ends throughconductors 92. The conductors 90 and 92 are connected to a valve 94 towhich pressure is supplied through a conductor 96. The valves 94 aresolenoid-operated in one position to connect the conductors with theconductor 96 and in the other position to connect the conductors 92 withthe conductor 96. The solenoids are electrically activated by a switch98 mounted on the pedestal 12 beneath the rocker arm 16 in a position tobe engaged by an adjustable screw 100 mounted on the underside of therocker arm, the adjustment of which will determine when the switch 98 isactivated.

As pointed out above, the metering means 46 are independently operableso that it is possible to supply different quantities of plastisol, forexample, a large quantity to one pair of nozzles 10 for large boots anda smaller quantity of plastisol to the other pair of nozzles 10 forsmaller boots. If different quantities of plastisol are discharged fromthe two pairs of nozzles, it is apparent that discharge through the pairto which the smaller quantity of plastisol is supplied will be completedbefore discharge through the other pair. Since the valves, as relatedabove, are not closed until the rocker arm 16 is elevated, the nozzlesthrough which the smaler quantity of plastisol has been injected, remainopen, while plastisol continues to be discharged from the other nozzlesand may drip due to draining of the plastisol clinging to the interiorof the conductors 56, or to a check valve which does not seat tightlyenough so that plastisol escapes around it into the conductors 56. Toremedy and prevent such possible drip in the event of a faulty checkvalve, a limit switch LS is provided for each metering device which isoperable, when the piston in the chamber 46a reaches the end of itsdischarge stroke, to effect closing of the valves in the nozzlesassociated with the metering means even though the rocker arm 16 isstill in its depressed position and hence still engaged with the switch98. As herein illustrated, a switch LS is mounted on each bracket plate61 adjacent the piston rod 64 and a part 63 is mounted on the piston rodso that it actuates the switch LS when it reaches the upper end of itsstroke which corresponds to the completion of the discharge stroke ofthe piston in the chamber 46a.

In normal operation of the apparatus a programming switch is selectedwhich corresponds to the amount of plastisol desired and is activated torotate the correct gauging pin into position beneath the lower end ofthe piston rod 64. Following this presure is supplied to the upper endof the chamber 46b to drive the piston down wardly therein against thepin which at the same time by lowering the piston in the chamber 46ainducts the desired amount of plastisol. The pressure is now reversed inthe chamber 46b to drive the latter upwardly and correspondingly thepiston in the chamber 46a to eifect discharge of the plastisol from thechamber to the nozzles and simultaneously the slide plate and rocker armmove forwardly and downwardly to bring the nozzles into a position abovethe upper ends of the molds and to activate the switch 98 so as to openthe valves. Air is again supplied to the upper end of the cylinders 26and 28 to move the nozzles to their inoperative position.

I claim:

1. Injection apparatus for delivering a measured quantity of plastisolinto the open top of a hollow mold comprising a nozzle containing avalve, first means connected to the valve for opening it, metering meansconnected to a source of plastisol and to the nozzle operable to inducta predetermined quantity of plastisol from the source, said meteringmeans being further operable to inject said inducted quantity ofplastisol into the nozzle, second means for effecting operation of themetering means to inject said inducted quantity of plastisol into thenozzle, means supporting the nozzle for movement from a retractedposition to a position adjacent the open top of the mold, said meansembodying a rocker arm supported for tilting movement about a horizontalaxis and a slide plate mounted on the rocker arm for movement forwardlyand rearwardly on the arm toward and from the mold, third means foreffecting movement of the rocker arm and slide to present the nozzle tothe open top of the mold, and means operable to effect substantiallysimultaneous operation of said first, second and third means.

2. Injection apparatus according to claim 1, wherein said metering meanscomprises a pump having intake and discharge openings, check valvesassociated with the intake and discharge openings operable to permitplastisol to be drawn into the pump and to be discharged from the pumprespectively, and means for effecting operation of the pump.

3. Injection apparatus according to claim 1, wherein said metering meanscomprises a pump cylinder having intake and discharge openings, a pistonin the cylinder, intake and discharge valves connecting the cylinder respectively to the source of plastisol and to the nozzle, means foreffecting reciprocation of the piston to induce the plastisol throughthe intake valve on one stroke and discharge it from the cylinderthrough the discharge valve on the reverse stroke, and means forcontrolling the length of the induction stroke and hence the volume ofplastisol drawn into the pump cylinder.

4. Injection apparatus according to claim 1, wherein said metering meanscomprises a pump cylinder contain ing a piston operable, by movement inone direction, to draw plastisol from the source into the cylinder andin the opposite direction to discharge plastisol from the cylinder,means for controlling the length of the stroke of the piston in the onedirection comprising a plurality of gauge pins, and means for moving aselected one of said gauge pins into a position to limit the stroke ofthe piston in said one direction.

5. Injection apparatus according to claim 1, wherein said last means iselectrically operable, comprising a switch for effecting operation ofsaid electrically operable means, and means on the rocker arm operable,by downward movement of the rocker arm to a position such that thenozzle is adjacent the open top of the mold, to actuate the switch andby elevation of the rocker arm to de-active the switch.

6. Injection apparatus according to claim 5, wherein said means on therocker arm is a screw mounted thereon and adjustable relative thereto.

7. Injection apparatus comprising a support, a plurality of nozzlesmounted on the support for movement from retracted positions above andlaterally of the open tops of a plurality of hollow molds supported inupright positions to positions adjacent the open tops thereof, twometering means, a single conductor connecting each metering means tosaid source of plastisol, two conductors connecting each metering meansto each nozzle of a pair of nozzles for sup-plying a predeterminedquantity of plastisol to each nozzle, valves in the nozzles,power-operable means for effecting movement of the nozzles from saidretracted positions to said positions at the open tops of the molds, andmeans operable when the nozzles reach said positions adjacent the opentops of the molds to open said valves.

8. Injection apparatus comprising a support, a plurality of nozzlesmounted on the support for movement from retracted positions above andlaterally of the open tops of a plurality of hollow molds supported inupright positions to positions adjacent the open tops thereof, a

source of plastisol, metering means for supplying plastisol 6 to saidnozzles and discharging it therefrom, means connecting certain of thenozzles to one metering means and others of the nozzles to othermetering means, means operable to control said metering meansindependently to enable supplying different quantities of plastisol tothe different nozzles, valves in the nozzles, switch means operable bymovement of the nozzles away from the open tops of the molds to closethe valves, and means operable before the nozzles are moved away fromthe open tops of the molds in the event that one of said metering meanshas completed its discharge before another to cause said last-namedmeans to close the valves in the nozzles associated therewith.

9. Injection apparatus comprising a support, a plurality of nozzlesmounted on the support for movement from retracted positions above andlaterally of the open tops of a plurality of hollow molds supported inupright positions to positions adjacent the open tops thereof, a sourceof plastisol, plural metering means for supplying plastisol to saidnozzles and discharging it therefrom, means connecting certain of thenozzles to one metering means and others of the nozzles to othermetering means, means operable to control said metering meansindependently to enable supplying different quantities of plastisol tothe different nozzles, valves in the nozzles, first switch meansoperable by movement of the nozzles to said positions adjacent the opentops of the molds to open said valves, said switch means being furtheroperaable by movement of the nozzles away from the open tops of the moldto close said valves, and second switch means operable independently ofsaid first switch means to close said valves, and means movable by eachmetering means at the end of its discharge stroke to actuate said secondswitch means.

10. Injection apparatus comprising a combination rocker and slide platesupporting the nozzles for movement from a lateral elevated position toa position above the open tops of the molds, a plurality of meteringmeans, means connecting certain of the nozzles to one metering means andother nozzles to another metering means, means operable to effectindependent control of the metering means to enable supplying differentquantities of plastisol to the different molds, valves in the nozzles,first switch means operable by the rocker as it lowers the nozzles intoa position above the open tops of the molds, said first switch meansbeing operable when the rocker is elevated to close the valves, secondswitch means, one associated with each metering means, independentlyoperable to close the valves at the termination of the discharge strokeof the metering means with which they are associated, said meteringmeans each embodying a cylinder containing a piston rod, gauge pinswhich control the stroke by limiting movement of the piston rod, and apart on the piston rod movable into contact with the second switch meanswhen the metering means reaches the end of its discharge stroke to closethe valves of the nozzles associated therewith.

References Cited UNITED STATES PATENTS 2,769,573 11/1956 Miller 222309 X2,834,051 5/1958 Kekettye 1830 3,095,126 5/1963 Willshaw 222-4343,231,136 1/1966 Rotter et a1. 222-309 X 3,341,076 9/1967 Wasilewski222309 X ROBERT B. REEVES, Primary Examiner H. S. LANE, AssistantExaminer US. Cl. X.R.

